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gain an appreciation of the magnitude of these events that they estimated
between M w 7. 0 a n d 7.5. The ages of these three events, and the extent to which
theaqueduct spanning the fault had been offset or displaced, also allowed
them to determine that the fault had experienced a late Holocene slip rate of
6.8--7.0 mm yr 1 . The slip rate and extent of displacement suggest an average
recurrence interval for large earthquakes at this location of 550 years. The pass-
ing of 830 years since the last of these earthquakes highlights, firstly, that
thefault zone is not inactive and, secondly, the next large earthquake may
be imminent, or possibly overdue. Such detailed conclusions would not have
been possible from the otherwise excellent historical record.
The archaeo-palaeoseismic record of many seismically active regions of the
world can be investigated in a manner like that undertaken for the Syrian sec-
tion of the Dead Sea Fault where those lands have been occupied by ancient
cultures. Iran, for example, has a long history of human settlement including
along-written record from the mid-8th Century. However, published palaeo-
seismic records in Iran are rare which limits the use of the archaeoseismic
data. Berberian and Yeats (2001)notethat some of these limitations include a
lack of radiocarbon chronologies, the size of a destroyed area is poorly known
forspecific earthquakes, and it has been difficult to prove that an archaeolog-
ical site was occupied continuously in the period between severe earthquakes.
They do note, however, that estimating a maximum time interval between large-
magnitude earthquakes can compensate for this latter uncertainty. Other prob-
lems have included the discovery of too few sites that provide evidence of damage
from the same earthquake. This in itself prevents the mapping of meizoseismal
areas and estimation of the moment magnitudes (Berberian and Yeats, 2001)of
palaeoearthquakes. In the absence of palaeoseismic studies it can also be difficult
to determine whether earthquakes or other events such as sudden abandonment
of sites due to invasions, revolutions, climatic change or fire caused the damage
to archaeological sites.
Studies in the New Madrid seismic zone, USA, have combined the dating
of archaeological artefacts and liquefaction features to obtain a clearer seismic
history in the area (Saucier 1991;Tuttle and Schweig, 1995). The sand blows here
cross cut occupation horizons. Soil development in the liquefaction features is
subtle in many cases and would be hard to date accurately without the presence
of Native American cultural horizons and artefacts (Tuttle and Schweig, 1995).
Certain kinds or styles of damage to ancient buildings can also be indica-
tive of past large earthquakes. The structural integrity of ancient buildings
results from both static and dynamic effects. Static effects refer to building fail-
ure due to the weight of the construction itself without any external loading.
Dynamic failures are caused by external violent loads such as earthquakes and
other extreme events like wind, explosions, rock falls, floods and thunderstorms
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